1. Field of the Invention
The present invention relates to an image recording apparatus having a pack chamber loaded with an instant film pack which stores by stacking plural pieces of instant film sheets, which have a developer pool at a tip portion in a predetermined carrying direction, which have a latent image formed thereon by exposure, and which record an image visualized by subjecting the latent image to spreading of the developer in the developer pool, and carrying the instant film sheets stored in the instant film pack loaded in the pack chamber, and performing image recording on the instant film sheets.
2. Description of the Related Art
In the prior art, as an image recording apparatus described above, there is known a printer which records an image on an instant film sheet. A printer of this type is provided with a pack chamber loaded with an instant film pack in which plural pieces of instant film sheets are stacked and stored, a film door openably covering the pack chamber, and a display section which displays the number of remaining sheets in the loaded instant film pack. Recording of an image on the instant film sheet is performed by raking up by a claw the first instant film sheet of the instant film sheets in the pack chamber and carrying the instant film sheet by clamping with a pair of carrying rollers, irradiating to the instant film sheet three color lights in turn from a light emitting element having light emitting colors of red (R), green (G) and blue (B) to write a latent image on the instant film sheet, and then crushing by a pair of developing rollers a developer pool provided for the instant film sheet to spread the developer (for example, refer to Japanese Patent Laid-Open No. 2002-221761, U.S. Pat. No. 6,317,561B1).
In order to accurately and surely carry the instant film sheet, there is also proposed carrying rollers which carry the instant film sheet, and which is provided with protrusions at the portions corresponding to both end portions of the instant film sheet except the developer pool (refer to U.S. Pat. No. 3,271,048).
The printer disclosed in Japanese Patent Laid-Open No. 2002-221761 described above is provided with a total of four rollers including a pair of carrying rollers and a pair of developing rollers, which causes components for incorporating the four rollers to have a complicated structure for holding the rollers and springs pressing the rollers, and a metal mold for manufacturing such components also to be complicated, which is disadvantageous in cost.
Further, there is a demand for miniaturizing the printer as a whole. To this end, it is necessary to use small-diameter rollers, and to reduce the interspace between the carrying rollers and the developing rollers, which requires the extremely high accuracy of components and in assembling in order to excellently spread the developer.
Further, in the printer proposed in U.S. Pat. No. 6,317,561B1 described above, the portion of the carrying roller corresponding to both end portions of the instant film has a relatively large width size. For this reason, a large margin portion of the instant film sheet except a space (image forming area) for storing the developer with a predetermined thickness is needed in carrying the instant film, thereby making the use of an instant film sheet with a small size difficult. As s result, there is a problem that it is difficult to realize a thin and small printer.
Further, the carrying roller proposed in U.S. Pat. No. 3,271,048 described above is provided with protrusions in portions corresponding to both end portions of the instant film sheet, thereby enabling the instant film sheet to be accurately and surely carried. Thus, when a latent image is written on the instant film sheet by a light emitting element while the instant film sheet being carried, it is possible to prevent a striped unevenness in the image from being produced by the deviation in the timing of printing based on the fluctuation in feeding accuracy of the instant film sheet. However, since this carrying roller has plural spike-like protrusions formed by a punch unit on the peripheral surface of a metallic round rod, the feeding pitch of the carrying roller for carrying the instant film sheet is large, resulting in a state where an intermittent feeding occurs when an instant film sheet having a small size is used. Thus, it is difficult to apply the carrying roller of this type for a thin and small printer.
The present invention has been made in view of the above-described circumstances and provides an image recording apparatus in which the reduction of component costs and the improvement of accuracy are achieved in a printer having carrying and developing rollers.
The present invention also provides an image recording apparatus which is capable of suppressing the irregular feed of a recording medium to a small extent and which has a thin and small structure.